That grasp looks OK to me. The little pin in the center of the handle post is a tell-tale sign. And though Richard pointed out that the marked Mohawk is a little scarce, I'll add my .02 cents and say its very scarce - that stamped brake arm is darn tough to find. If I didn't have one I'd be all over this one.
Looking back at pictures of the dozen or so Pettengills I've had over the years, they've all had wooden grasps. My number 4 has the wire brake lever. That's a neat variation.